Oil heater



Feb. 10, 1925.

G. W. COEN OIL HEATER Filed April l5, 1921 3 Sheets-Sheet 1 Patented Feb. 10, 1925.

UNITED STATES GARNET W. COEN, OF SAN FRANCISCO, CALIFORNIA.

OIL HEATER.

Application filed April 13, 1921, Serial No. 461,078.

.. @YZ whom 'it may concern.'

Be it known that I, GARNET W. OUEN, a citizen ofthe United States, residing at the city and county of San Francisco and State of California, have invented new and useful Improvements in Oil Heaters, of "which the following is a specification.

This invention relates to liquid heaters, and especially to. a simplified form of the struct-ure shown in my copending application entitled Oil heater, filed March 30, 1921, Serial No, 157,008.

One of the objects of the present invention is 'to generally improve and simplify the construction of oil heaters, and especially to provide a structure Which will permit a maximum heat transfer to be obtained between the heating medium and the oil or liquid to be heated; thermal efliciency being obtained in this instance, first, by maintaining the oil in a ribbon or film-like condition during its entire passage through the heater; secondly, by maintaining the oil in the state of agitation and under comparatively high velocity; and third, by maintaining the steam or other heating medium employed at high velocity, and by maintaining the main volume of the steam in contact with the surfaces to be heated.

Another object of the invention is to construct a heater which may berreadily .taken apart for inspection, repairs, etc., but particularly for the purpose of cleaning the same, and Which When taken apart will present an exposed surface readily accessible for cleaning, scraping or otherwise.

Another object of the invention is to provide a heater which is simple, compact and substantial in construction, comparatively cheap to manufacture, and in Which all parts are free to expand Without danger of imposing unnecessary strains on the connected parts; further to connect the several pipes leading to and away from the heater in such a manner that stuffing boxes or similar connections may be entirely eliminated. A

Further objects Will hereinafter appear.

The invention consistsy of the parts and the construction, combination andarrangement of parts as hereinafter more fully described and claimed, having reference to the accompanying drawings, in Which- Fig. 1 is a side elevation of the heater partially in section.

Fig, 2 is a pla-n view of the same,

Fig. 3 is a cross-section on line 3 8, Fig. 1.

- Fig. 4 is a central vertical section of the heater showinga slight modification thereof.

Orude oils such as employed today for fuel purposes, and particularly crude oils derived from an asphalt base, are becoming thicker and more viscous as time passes due to the heavy extraction of gasoline, kerosene and other products. Crude oils of this character when obtained from the refiners are often so thick and` viscous that the oil must be heated to a temperature from 200 to 300o F., and sometimes even more, before it is rendered sufliciently liquid to be readily handled and efciently atomized by the burners. The heating of fuel oil is therefore not only a necessity, due to the reasons specified, but it also represents more or less of a problem in actual practice as the heaters rapidly lose their efficiency due to the formation of deposits of carbon, asphalt, sand, etc., Which rapidly accumulate and adhere tof the heating surfaces. Such deposits are, practically speaking, non-conductors of heat and they form a. coating which bakes and hardens on the heating surfaces, and furthermore gradually clogs the passages through which the oil is forced. It can, therefore, be readily seen that unless such accumulations are removed from time to time that the heater will become so neiiicient as to be practically useless.

Havingthese problems and conditions to encounter in actual practice, 1 have developed a heater which is particularly adapted to handle crude oils such as referred to, and which will efficiently heat a given volume of oil if cleaned, from time to time. One of the main features of the present invention is, therefore, the provision of a heater which permits a maximum heat transfer at all times, and which can be readily and quickly taken apart for Acleaning whenever necessary; further a heater in which the steam or heating medium employedmay beutilized to obtain the greatest thermal efficiency possible. I Vhave accordingly constructed a heater consisting of a series of interspaced cylindrical casings mounted one Within the other as indicated at 2 and 3. These casings are interspaced as shown to form a liquid flow passage 4i and acentrally disposed heating chamber 5. The outer shell op casing 2 is Cil closed at its upper' end by means of a head member 6, welded or otherwise secured thereto as at 7. The lower end of this casing is provided with an annular Harige 8, which is also secured by welding as indicated at 9 and 10. The flange is otherwise drilled to permit insertion ol bolts 11, the function oi which will hereinafter be described. The inner shell or casing 3 is similarly provided with a head member l2, preferably welded as at 13. The lower end ot the casing is supported by a head mem` ber 14 and is welded thereto as at 15. The inner casing is furthermore provided with a vfalse bottom section 16, also welded thereto as at 17; said bottom section being interspacedv with relation to the main head 1111, as indicated at 18. The main head 1a is drilled so that the holes will align with the bolt holes formed in the flange 8, and the main head is therefore secured to the flange 8 by means ot the bolts 11' shown.

Surrounding the inner shell 3 is spiral shaped spacing member 19. This member is welded or other-wise securedto the innerV shell, and it serves two functions, first that of maintaining the spacing between the shells and maintaining them concentric with relation to eac-h other, and secondly, that of forming a spiral shaped passage through which the oil or liquid to be heated must pass during its flow through, the heater. The inlet for oil is formed at the point indicated at 20@ This inlet may be connected with a pipe not shown, with a pump which will force the oil through the heater with comparatively high velocity. The oil, in

other words, enters the lower end ot the spiral shaped passage and discharges fromv the upper end oitl said passage to a chamber 21 formed between the head members G and 12, and is finally discharged. through a pipe 22, welded or otherwise secured in the upper head member 6.

The lower or main head member 14 is provided with twoyopenings through which passes a steam inlet pipe 23, and an outletpipe 24. The inlet pipe is connected with a boiler or other suitable source of supply, while the discharge pipe 24, through which the condensate discharges, is connected with a trap or other means not here shown. Both pipes are welded to the inner head member 16 and. thereby the necessity ot employing stuffing boxes or the like to prevent leakage is eliminated. The upper end of the pipe 23 terminates in a goose-neck and it is held in central position within the chamber 5 by means ot a spider 26. See Figs. 1 and 3. This spider also serves as a support for a coneshaped spreader 27, against which the steam impinges when admitted. This spreader detlects the steam which enters at a high velocity against the inner wall of the shell Sand thereby causes` the main Volume of steam to travel rdown the inner surface of the shell in intimate contact therewith and at high velocity; this being an important feature as it constantly wipes off or removes any condensate which forms and which might collect, thereby maintaining the surface in a condition where maximum heat transfer can take place. It furthermore deliects the main volume of steam to the point or area where actual heat transfer takes place, thus further increasing the thermal elhciency ot' the heater in" general.-

In Fig.l 4, I have introduced an inner shell, suc-has indicated at 28. This shelll terminates in a cone-shaped cover section 29 disposed directly below the discharge end or" the inlet or goose-neck 25. Thissliell may be constructed ot' comparatively thinsheet iron as it is perforated, asf at 30, to prevent formation of a pressure chamber exterior thereof. The shell is of smaller diameter than the interior shell 3 and as such formsy an annular passage 81 through which the lnain volume of" steam flows before it conrdenses and reaches the discharge pipe'24f; concentric positioning V"et the shell-28 being obtained, by forming a plurality ot spacing lugs on the exterior thereof as Vindicated at 32.

In actual practice I rind that` the greatest heattranster is obtained. when the incom ing steam is maintained at high velocity, and when intimate contact is maintained between the ste-am and the heating or t-ransferring surface. This is efficient-ly accomplished by the. structure shown in Fig..

1, but is even more efficiently accomplished by inserting` shell 28, shown in Fig. 4., that is the shell there shown `not only lforces thel steam discharging from the goose-neck 25 outwardly against the inner surface ot the shell 3', but it also maintains the main volume of steam in intimate Contact therewith, thus doing awayv to a largeV extent with the dead space'tormed in the center of the chamber 5. This dead7 space is also formed-in the shell 28, but no circulation ot steam. is. maintained within this chamber,

due to the tact that the perforations permit sufficient amount ot steam to enter to balance t-he pressures.

The present heater is in reality a simplilied form ot the structure shown iu my copending application referred to. The pres* ent heater is known as a one-way heater as the oil only passes through a single passage betere it is discharged.

l? rom the foregoing it willi be obvious that the oil to be heated is delivered to the inlet 20 of the heater-through a pipe or other suitable means not here shown, which is connected with apump-or similar device. This pump maintains a certain pressure on the oil and this-pressure is preferably such that CII the oil will travel through the heater at a comparatively high `fclocity. The oil enter-v discharges through a pipe 22. The oil during its entire passage through the `heater will be maintained in a ribbon or film-like condition. lts velocity throughout will, practically speaking, be maintained constant and as the velocity is fairly high and the path or passage tortuous, it is obvious that sufi'icient agitation will be obtained to thoroughly mix and uniformly expose the entire oil body to the heating surface presented. The heating surface presented by the` inner shell 3 is maintained at maximum efficiency, first, by the high velocity of the steam impinging and travellingy downwardly against its inner surface, and. secondly, by the wiping action of said stean'i.

rllhe heater constructed as illustrated in the present instance is very compact and substantial. The several casings employed are preferably cylindrical and as such may be easily fitted and nested one within the other. The inner casing or shell 3 is entirely supported by the main head member 14 and as such is free to expand upwardly without imposing any strain on the exterior shell. The shell 2 is also supported by the main head member and it also is free to expand in every direction without imposing any strain on the inner shell. The joint forn'ied between the flange S and the main head 14 is preferably maintained by a gasket as shown, and is in fact the only packed `ioint required in the whole heater.

To further increase the thermal elliciency of the heater, and more particularly to prevent conduction and radiating heat losses, an exterior jacket "L is employed. This jacket supported by the flange 8 at the lower end and by a ring shaped flange 31 at the upper end, which is merely slipped over the. shell 2; the space formed between the jacket Q0 and the shell 2 being filled with a non-conducting packing. such as asbestos or the like.

In actual practice, if it is desired to clean the heating or exterior surface of the shell il, it is only necessary to remove the bolts 11 and to break the unions on the pipes 28 and 2l. The main head 14 supporting the inner shell 3 and the inlet and outlet pipes 23 and 2l may then be extracted. When so eX- trac-ted it is obvious that the entire exterior surface of the shell 3 is so exposed that it may be quickly and readily cleaned to remove any adhering deposits, whether they be hardened, baked or viscous in nlature; furthermore the entire inner surface of the shell 2 is also exposed so this can be quickly cleaned if necessary. Actual practice shows however that no accumulation forms on this surface as it is not exposed to the direct heat of the steam. ll? ith the surfaces cleaned, it is only necessary to re-insert the shell 3, being careful however that a gasket is interposed between the flange. 8 and the head 14- before thc bolts 11 are placed and tightened. The unions on the pipes 23 and are then connected and the heater is again ready for use yThe provision of the inner bottom or head section 16 is an important feature; first, because it balances the pressure of the steam between the head and bottom sect-ions 12 and 16, thereby relieving the head 14 of this pressure, and secondly7 because it permits welding of the pipes 23 and 24, thereby eliminating the use of stuffing boxes, etc. The use of the inner bottom section 16 is of further importance as it materially strengthens the lower head and particularly the annular flange formed thereon. This is an advantage as it permits the head to form a continuous beam between the opposing bolts 11, thereby reducing the bending strains.

llfhile certain features of the present invention are more o-r less specifically illustrated, I wish it understood that various changes in form and proportion may be resorted to within the scope of the appended claims, similarly that the materials and finish of the several parts employed may be such as the experience and judgment of the manufacturer may dictate or varying uses may demand.

Having thus described my invention, what I claim and desire to secure by Letters Patent is 1. ln a heater of the class described, a head member provided with a4 marginal flange and also having a steam inlet passage and condensate outlet therethrough, a shell permanently connected to said head member, a second shell having an outwardly directed flange at its lower end to rest upon the marginal flange of the head member, said shells being spaced to provide a narrow oil passage between them, an enclosing shell permanently connected to the periphery of the flange of the. second shell, closures for the upper ends of the first and second shells, the second shell having an outlet', the enclosing shell having an inwardly directed annular flange at its upper end embracing the upper end of the second shell, and means for deta-chably securing the flange of the second shell to the flange of the head member whereby the second shell and .the enclosing shell and flange at the upper end of the latter may be removed as a unit from cooperative relation with the first shell to expose the co-operative surfaces of the oil passage for cleaning purposes.

2. In a heater of the class described, a head member provided with amarginal flange and also havinO' a steam inlet )assa-O'eb b b and i a Acondensate' outlet-A therethrough,VY a shelly permanently connected: to said head member, a second Shell' having an outwardly directd vflange at its lower end whereby to support the second shell onl the marginal a spiral shaped oil passage, an enclosing she-ll permanently connected to .the periphery of the flange ofthe second shell and spaced from the latter, the enclosing shell having an inwardly.directed annular flange at its upper end which embraces `the upper endl of the seco-nd shell, and means for detachably securing the lange of the seco-nd shell io the flan-ge of said head 1nember whereby the second shell and the enclosingv shell and the ange at the upper end of the latter may be removed as a unit from co--operalnive relation with the first shell to expose co-operative surfaces of the oil passage for cleaning purposes.

G'ARNET XV. COEN. 

